Related Experiment Video
Updated: Jun 20, 2026
07:17
Evaluation of Fluid Overload by Bioelectrical Impedance Vectorial Analysis
Published on: August 17, 2022
Caffeine ingestion and fluid balance: a review
1School of Sport and Exercise Sciences, Loughborough University, Leicestershire, UK. r.j.maughan@lboro.ac.uk
Summary
Regular consumption of caffeinated beverages does not negatively impact hydration. Tolerance develops to caffeine
Area of Science:
- Physiology
- Nutrition Science
Background:
- Caffeine and methylxanthines are known diuretics.
- Consumers are often advised to limit caffeinated drinks when fluid balance is critical.
Purpose of the Study:
- To review literature on caffeine's effect on fluid balance.
- To provide evidence-based recommendations on caffeinated beverages for optimal hydration.
Main Methods:
- Medline database search (January 1966-March 2002).
- Keywords: tea, coffee, caffeine, diuresis, fluid balance, water-electrolyte balance.
- Secondary search using bibliographies of identified articles.
Main Results:
- Large caffeine doses (250-300 mg) can acutely increase urine output in non-habitual consumers.
- Tolerance to caffeine's diuretic effects develops with regular consumption.
- Standard servings of caffeinated beverages show no significant diuretic action.
Conclusions:
- Ecologically valid studies do not support claims of fluid loss from normal caffeine consumption.
- Caffeine-containing drinks do not lead to poor hydration status in a typical lifestyle.
- No clear evidence necessitates avoiding caffeinated drinks when fluid balance is a concern.
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